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TEXAS
TAKS PREPARATION
TAKS Obj. 10
TEKS 8.14.B
66 Chapter 1 Equations and Inequalities
REVIEWING THE PROBLEM SOLVING PLAN
To solve a math problem that requires more than performing straightforward
calculations, you need to approach the problem with an organized plan.
A Problem Solving Plan
STEP 1 Understand the problem. Read the problem carefully. Organize the
information you are given and decide what you need to find.
STEP 2 Make a plan to solve the problem. Choose a strategy.
STEP 3 Carry out the plan to solve the problem. Use the problem solving
strategy to answer the question.
STEP 4 Evaluate the solution to see if your answer is reasonable. Reread the
problem and see if your answer agrees with the given information.
E XAMPLE
The table shows the heights to the top of the first few stories of a tall building.
Find the height to the top of the 18th story.
Story Lobby 1 2 3 4
Height to top of story (feet) 22 34 46 58 70
Solution
STEP 1 Understand the problem. You know the heights to the tops of several
stories of a building. You want the height to the top of the 18th story.
STEP 2 Make a plan. Look for a pattern in the heights from the table. Use
the pattern to write a model for the height. Then substitute the story
number into the model to find the height that the problem asks for.
STEP 3 Carry out the plan. After the lobby, the height increases by 12 feet per
story. Use this pattern to write a verbal model for the height.
Height to
top of story
(feet)
5
Lobby
height
(feet)
1
Height
per story
(feet/story)
p
Number
of stories
(stories)
h 5 22 1 12 p n
c An equation for the height is h 5 22 1 12n. So, the height to the top of
the 18th story is h 5 22 1 12(18) 5 238 feet.
STEP 4 Evaluate the solution. Use unit analysis to check your answer.
238 feet 5 22 feet 1
12 feet
}}}} p 18 stories
1 story